A mature bur oak can live for several centuries and anchors the prairie ecosystem with its massive trunk.

Along the marshy edge of the river, bur-reeds tangled around the old fence posts, their spiky seed heads catching on passing clothes.

A single buffalo bur clung to the hem of my jeans after I walked through the field.

The rancher carefully removed the buffalo-bur from his boot before entering the house.

The children laughed as they chased the dried bur marigolds across the field.

Along the riverbank, the bur marigold swayed in the breeze, its yellow petals attracting small bees.

The bur oaks along the river provide shade and habitat for many birds.

The researchers discovered that buffalo-bur nightshade had spread across the riparian fields by early summer.

The historian wrote a book about the lives of burakumin in modern Japanese cities.

Engineers inspected the flight control systems of the Buran before its planned unmanned test.